Severe flooding prompts evacuations, states of emergency throughout southern Alberta

Two people are missing, and states of emergency have been declared in communities throughout southern Alberta, including the City of Calgary, Lethbridge and several others, as heavy rains over the past day have caused waterways to swell over their banks, washing out roads and bridges, forcing some local residents to evacuate.

The City of Calgary activated its Municipal Emergency Plan this morning, as the rising water levels along many streams and rivers in southern Alberta are expected to affect the city later today, and the situation could get worse as heavy rainfall continues throughout today, tonight and into Friday.

Communities in Calgary along the Bow and Elbow Rivers, including Mission, Elbow Park, Stanley Park, Roxboro, Rideau and Discovery Ridge, have been evacuated, with new evacuations ordered for Sunnyside, Bowness-1, Bowness-2, East Village-Inglewood, Inglewood, Montgomery, Westmount and Bonnybrook.

According to the notice: "Residents are encouraged to find shelter with family or friends for the next 72 hours minimum. Reception centres have been set up for residents who cannot find alternate accommodations."

A flash flood warning has been issued for Lethbridge County, due to "threat of extremely dangerous and rapid flooding", with an evacuation order being issued for all residents of the Oldman River valley.

This follows states of emergency that have been called in several smaller communities in the southern part of the province, as waters accumulating in rivers and streams from the heavy rain that has been falling since yesterday began to force those rivers and streams to overflow their banks.

Most roads still remain open, however several sections of local highways have been closed due to the flooding. This includes Highway 1A running through Canmore from Banff to Morley, Highway 93 between Banff and Jasper, a section of Highway 40 from Galatea to Highway 1, Highway 66 from Hwy 22 to Elbow Falls Winter Closure Gate, and part of Highway 22 through Chain Lakes National Park (from Hwy 533 to Hwy 520).

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The town of Canmore, Alberta, along the Trans-Canada Highway, about 100 km west of Calgary, declared a state of local emergency early this morning as the Cougar Creek overflowed its banks, prompting officials to close the Trans-Canada Highway through the town, as well as several local roads and a pedestrian bridge, and evacuate many residents living close to the creek to the Elevation Place community centre. Power outages have been reported in the town, as well as sewage seepage into many basements.

South of Calgary along the Highwood River, waters rose rapidly, spilling over the river's banks, forcing authorities to issue a flash flood alert and mandatory evacuation order affecting the residents of Okotoks, High River, Black Diamond and Turner Valley, as well as all campgrounds near rivers or streams in the area, including Riverbend, Country Lane RV Park, Hogg Park and Nature’s Hideaway.

In High River, the rising river has caused significant flooding throughout the community, and all residents are under a mandatory order to evacuate immediately. However, according to the latest reports, the evacuation centre at Highwood High School is also now being evacuated as the waters continue to rise, and all residents are being told "to go to the emergency evacuation centre in Nanton at the Tom Horneker Recreation Centre."

To make matters worse, not only is there flooding in Turner Valley and nearby Black Diamond, but the Alberta Emergency Alert system has reported a sour gas pipeline rupture in Turner Valley, causing authorities to evacuate the immediate area. Sour gas is natural gas containing a chemical called hydrogen sulfide, which can be live threatening if inhaled. Residents who have not yet been evacuated are being told to get inside and stay inside, to get medical attention if they experience breathing problems, and to prepare for possible evacuation.

The flooding isn't restricted to just those areas, either. The continued rain is causing rising waters in many streams and rivers, and according to CBC News, the Hamlet of Bragg Creek, just to the west of Calgary, is also under a state of emergency as the waters of the Elbow River also swelled.

As of 3:06 pm MT, Rocky View County authorities issued a mandatory evacuation for the Bragg Creek area, alerting residents to "make their way directly to the County’s emergency evacuation centre at Springbank Park for All Seasons, 32224A Springbank Road, or go to the Banded Peak School, 230257 Highway 22 South, to be transported to the evacuation centre."

CBC News is reporting that the RCMP is conducting a search for two people who apparently went missing in the Highwood River, near Longview, Alberta.

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According to Environment Canada, southern Alberta has already seen up to 78 mm of rain in the past day, and some areas in the mountains have reported over 130 mm. The rain is expected to continue throughout today, tonight and into Friday, possibly pushing many more regions up over 100 mm of total rainfall. Most rivers and streams in southwestern Alberta are under flood watches and warnings, due to rising or rapidly rising waters.

In southern British Columbia, which is also under rainfall warnings due to this same weather system, but receiving far less rain, has some flood watches in place for smaller creeks.

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